MOLLUSCA FROM THE SOUTHERN SUDAN. 241 



Subgenus Lanistes, Montfort. 

 Lanistes innesi, Pallavy. 

 Lanistes innesi, Paliaiy, 1902, Bull. Inst. Eg-ypt. ser. iv. uo. 3, p. 91, pi. 1. fig. 2. 



Fourteen specimens were found at a short distance from the mouth of the 

 Bahr el-Zanifa, all dead, onlj one with the epidermis well preserved and 

 three with fragments of it. The umbilicus varies in different individuals ; in 

 two it is completely covered by the reflection of the inner lip, in two 

 uncovered, and in the rest it is partially covered. It greatly resembles 

 L. purjnireus, Jonas {Ampidlaria purpurea, 1839, Archiv f. Naturgesch. 

 vol. i. p. 342, pi. 10. fig. 1), and may be a variety of that species. It is dis- 

 tinguished by the spire having the contour less flattened, the whorls more 

 convex, sutures deeper, and the lines of growth coarser. The height of the 

 spire varies somewhat ; the best preserved specimen measures alt. 51*5, diam. 

 40 mm. ; whorls six. The largest measures alt. 56, diam. 40 mm.; whorls 

 seven. 



The holotype was obtained by Dr. Innes Bey on the White Nile, but the 

 exact localitv is not given. I have seen the shells in the British Museum 

 (Nat. Hist.) taken by Captain Flower in ih.Q Bahr el-Zarafa which were 

 referred by him to L. pmrpureiis, and 1 find that they are conspecific 

 with L. innesi, Pallary. 



Family Melaniid^. 

 Genus Melania, Lamarck. 



Melania tuberculata, MiiU. 



Nerita tuberculata, Miiller, 1774, 'Verm. Terr, et Fluv. sen Anim. Infus., Uelmiii. et 

 Testae, non Marin., Succ. Hist.' vol. ii. p. 191. 



This widely distributed species was taken near Mogran, at Ad-Duwem, 

 Tawila, Masran Island, Gebel En, Kilka, near Melut, in Lake Shambe, where 

 it was especially numerous, and at Gondokoro. 



All the specimens are decollated except a few very young ones which have 

 the protoconch preserved. 



Order PULMONATA. 



Suborder BASOMMATAPHORA. 



Family Limn^id^. 



Genus LiMN^EA, Lamarck. 



LlMN^EA CAILLIAUDI, Bourg. 



Limncea cailliatidz, Bourguignat, 1883, ' Hist. Mai. Abyssiuie,' pp. 89, 90, figs. 100-101. 



Five living specimens were found : at Gebel En (two), Bahr el-Zarafa (two), 



